Add peppers and celery to pan, reduce heat to medium and stir-fry 3 minutes, or until peppers are crisp-tender. Add scallions and ginger and stir-fry 3 minutes, or until scallions are tender.

In small bowl, whisk together broth, chili paste, and reserved marinade. Pour into pan and bring to a boil. Reduce heat to low, return pork to pan, and cook 1 minute, or until sauce is lightly thickened and pork is heated through.